Nr-CWS promotes MSC secretion of exosomes with higher biological activity

Objective To explore the production of exosomes secreted by mesenchymal stem cells and enhance their biological activity to promote healing and regeneration. Methods Mesenchymal stem cells were cultivated with Nocardia rubra cell wall skeleton and to extract exosomes. Then, the morphology of exosomes and surface marker proteins were identified and the amounts of exosomes were measured. The proliferation and migration of human dermal fibroblasts were detected by CCK-8 and scratch assays, and the capacity of exosomes to promote the regeneration of human umbilical vein endothelial cells was detected by in vitro angiogenesis assay. Results Cultivating mesenchymal stem cells with Nocardia rubra cell wall skeleton greatly increased the production of exosomes by mesenchymal stem cells, while the classical morphology of exosomes and surface marker proteins were not altered. Moreover, we detected the enhanced capacity of exosomes to promote the proliferation and migration of human dermal fibroblasts and the regenerationof human umbilical vein endothelial cells. Conclusions Nocardia rubra cell wall skeleton can improve the production of exosomes by mesenchymal stem cells and enhance their biological activity to promote healing and regeneration.